In a small saucepan, combine 1 cup white sugar and 1 cup of the 6 cups cold water. Heat over medium heat, stirring occasionally, until the sugar has completely dissolved and a simple syrup forms. Remove from the heat and allow the syrup to cool.
In a large pitcher, combine 1 cup fresh lemon juice, the cooled simple syrup, and the remaining 5 cups cold water. Stir until well combined.
Add 1 teaspoon blue food coloring and stir until the color is evenly distributed throughout the lemonade.
Add ice cubes to the pitcher to chill the lemonade or refrigerate until ready to serve.
When serving, pour the blue lemonade into glasses filled with ice. Garnish each glass with a slice of lemon and a sprig of fresh mint.
Notes
- Make sure the sugar is totally dissolved when you're making the simple syrup so your lemonade doesn't end up gritty.- Let the syrup cool completely before mixing it with the lemon juice to avoid watering down the lemonade.